1. Technical Field
The present invention relates to a gear box for a wind turbine generator and the wind turbine, especially the gear box and the wind turbine using the gear box which increases the rotation speed and outputs the increased rotation speed from blades to a generator side via a main shaft.
2. Description of the Related Art
In recent years, from a view point of preserving the global environment, the use of wind turbine generators to generate reusable energy has become popular.
In general, a wind turbine generator comprises a rotor head equipped with blades, a nacelle accommodating a drive train and a rotation axis, and a tower supporting the nacelle. Herein, the drive train is provided for transmitting torque from the rotor head side to the generator side and usually the gear box is integrated therein so as to increase the speed of the rotor head and input the increased speed to the generator.
As a gear box for a wind turbine generator, a planetary-type gear mechanism as disclosed in Patent Document 1 is well known. In the planetary gear mechanism, a plurality of planet pins are provided on a carrier which rotate with a main shaft of the rotor head side, and planet gears are supported to the planet pins via planet bearings and a ring gear and sun gear are meshed with the planet gears. With this, as the main shaft rotate on the rotor head side, the planet gears rotates and revolves around planet pin and the increased speed is outputted to the sun gear side.
In the view of improving the life of the bearing, the lubrication oil must be supplied to the planet bearings in the gear box.
Regarding this point, in the gear box disclosed in Patent Document 1, an oil bath for reserving the lubrication oil is provided under the housing and the planet bearings pass through the oil bath and are lubricated when the planet gears revolve. Furthermore, a lubrication oil supply path is formed inside the planet pin and the lubrication oil being injected through the nozzle is supplied to the planet bearing via the lubrication oil supply path.